feat: native folder picker button via tkinter

server.py

@@ -44,6 +44,20 @@ def serve_frontend():
     return FileResponse("index.html")
 
 
+@app.get("/pick-folder")
+def pick_folder():
+    import tkinter as tk
+    from tkinter import filedialog
+    root = tk.Tk()
+    root.withdraw()
+    root.attributes("-topmost", True)
+    folder = filedialog.askdirectory(title="Ordner auswählen")
+    root.destroy()
+    if not folder:
+        raise HTTPException(status_code=204, detail="Kein Ordner ausgewählt")
+    return {"folder": folder}
+
+
 PREVIEW_ALLOWED_EXTENSIONS = {".jpg", ".jpeg", ".png"}